A spring clamp is mainly used to firmly and tightly clamp two work pieces together to facilitate subsequent fabricating or machining of the work pieces. For example, two planks may be clamped together using the spring clamp and then drilled or cut. Most of the currently available spring clamps do not have any auxiliary locating mechanism provided on or between two handles thereof, and are subject to unexpected loosening from the work pieces clamped between two jaws of the spring clamps due to an overlarge vibration produced during drilling or cutting the work pieces. The conventional spring clamps therefore have adverse influences on machining quality and efficiency.
To overcome the above-mentioned problem, there has been developed an auxiliary locating mechanism for mounting between two handles 11, 12 of the spring clamp, as shown in FIG. 9. However, the auxiliary locating mechanism has a control lever that occupies a considerably large space. Moreover, the control lever is fixed at a proximal end to the auxiliary locating mechanism with rivets or screws and nuts. Since the space between the two handles 11, 12 of the spring clamp is small, it is uneasy and therefore time-consuming to assemble the control lever to the auxiliary locating mechanism in the above manner. The spring clamp with the conventional auxiliary locating mechanism therefore requires relatively high manufacturing cost while the productivity thereof is low.
It is therefore tried by the inventor to develop a spring clamp having an elastically operable locating mechanism that is structurally simple and compact, functionally improved and practical for use, as compared with the conventional auxiliary locating mechanism.